Neural stem cells promote glioblastoma formation in nude mice.

PURPOSE: Neural stem cells (NSCs) have been characterized with the ability of self-renewal and neurogenesis, which has inspired lots of studies to clarify the functions of NSCs in neural injury, ischemic stroke, brain inflammation and neurodegenerative diseases. We focused on the relationship of NSCs with glioblastoma, since we have discovered that recurrent glioblastomas were inclined to be derived from subventricular zone (SVZ), where NSCs reside. We want to clarify whether NSCs are involved in glioblastoma relapse. METHODS: Immunocytochemistry was used to confirm the stemness of NSCs. The Cell Counting Kit-8 was used to measure the proliferation of cells. Migration abilities were examined by wound healing and transwell assays, and tumor formation abilities were confirmed in nude mice. RESULTS: We found in experiments that NSCs promoted proliferation of a glioblastoma cell line-Ln229, the migration ability of Ln229 cells was motivated by co-cultured with NSCs. Tumor formation of Ln229 cells was also accelerated in nude mice when co-transplanted with NSCs. In immunohistochemistry, we found that the Sox2- and Ki67-positive cells were much higher in co-transplanted groups than that of control groups. CONCLUSIONS: These results imply the potential role that NSCs play in speeding up tumor formation in the process of glioblastoma relapse, providing the basis for dealing with newly diagnosed glioblastoma patients, which may help postpone the recurrence of glioblastoma as far as possible through preprocessing the tumor-adjacent SVZ tissue.

Population genetic structure and historical demography of the ground beetle Chlaenius costiger in the Tsinling-Dabashan Mountains of central China.

Population genetic structure and demographic history of the ground beetle Chlaenius costiger (Coleoptera: Carabidae) in the Tsinling-Dabashan Mountains of central China were estimated using mitochondrial DNA sequences (Cox1-tRNALeu-Cox2) of 144 individuals from 16 local populations. The high haplotype diversity was accompanied by low nucleotide diversity. Phylogenetic analysis (Bayesian inference) of the 43 haplotypes revealed no phylogeographic structure. Analysis of molecular variance suggested that most of the variation was attributed to within population variation (79.26%). Mantel test results showed a significant correlation between the genetic distance and geographical distance of the populations with a correlation coefficient equal to 0.216964 (P = 0.0471 < 0.05), indicating the presence of isolation by distance. Spatial AMOVA and PERMUT analyses showed no phylogeographic structure. Gene flow calculated through the number of migrants was high between many pairs of populations. The results of a neutrality test, mismatch distribution analyses, and Bayesian skyline plot analysis together showed a demographic expansion. The estimated expansion time of the whole sampled population was 0.125 million years. The complex topography in the Tsinling-Dabashan Mountains area led to the high level of genetic diversity, and migratory flight resulted in the high level of gene flow, leading to the lack of a phylogeographic structure.

Functional polymorphisms in microRNA gene and hepatitis B risk among Asian population: a meta-analysis.

Genetic mutations in microRNA gene can alter expression, which may interact to increase the risk of developing various diseases, including hepatitis B. However, published results are inconclusive or ambiguous. The aim of this review and meta-analysis is to more precisely estimate the association between polymorphisms in microRNA genes and hepatitis B risk. A digital search was performed of the MEDLINE EMBASE, CNKI, and CBM databases to identify relevant articles published up to February 18, 2014. Ten case-control studies were included, with a total of 6042 patients with hepatitis B and 6834 healthy controls. Nine single-nucleotide polymorphisms in the miRNA gene were examined, including miR-34b/c [rs4938723 (T>C)], miR-196a-2 [rs11614913 (C>T)], miR-146a [rs2910164 (G>C)], miR-499 [rs3746444 (T>C)], miR-122 [rs3783553 (ins/del)], miR-149 [rs2292832 (C>T)], miR-106b-25 [rs999885 (A>G)], miR-let-7c [rs6147150 (ins/del)], and miR-218 [rs11134527 (A>G)]. The meta-analysis results indicated that the miR-196a-2*T, miR-122*del, miR-106b-25*A, and miR-let-7c*del alleles/carriers increase the risk of hepatitis B among the Asian population. However, the miR-146a, miR- 499, miR-149, miR-218, and miR-34b/c polymorphisms may not be linked with the risk of hepatitis B. Further investigations are warranted to determine the exact associations between microRNA mutations and hepatitis B susceptibility.

Genetic diversity and historical demography of the narrow-range endemic Alpine toad, Scutiger liupanensis, in the Liupan Mountains of central China.

The genetic diversity and historical demography of the narrow-range endemic Alpine toad, Scutiger liupanensis, in the Liupanshan National Forest Park of central China were estimated using cytochrome b and cytochrome c oxidase subunit I (COI) from 85 individuals from five local populations. Both the haplotype diversity (Hd) and the nucleotide diversity (Pi) were very high. Phylogenetic analysis of the 63 haplotypes revealed two major clades, and an analysis of molecular variance attributed most of the variation to within populations. Mantel tests did not reveal an isolation by distance pattern of genetic divergence between populations, and SAMOVA showed no phylogeographic structure. The results of neutrality tests, mismatch distribution analyses, and allelic frequency spectra suggest that a sudden demographic expansion occurred, and that high genetic variation is beneficial to the survival and development of this species.

Effect of Ginkgo biloba extract on matrix metalloproteinase-3 expression in a rat model of chondrocyte injury.

A rat model with cartilage chondrocyte injury was established using interleukin-1ß (IL-1ß) to investigate the effect of Ginkgo biloba extract (EGb) on matrix metalloproteinase-3 (MMP-3) expression. Rat chondrocytes were extracted and randomly divided into six groups: control group, IL-1ß (model) group, IL-1ß + dexamethasone group, and IL-1ß + EGb group (both high and low dose groups). Reverse transcriptase polymerase chain reaction and enzyme-linked immunosorbent assay were used to detect MMP-3 expression. Compared to the MMP-3 mRNA level in the control group, MMP-3 mRNA level significantly increased in the model group (P < 0.05). The application of dexamethasone or EGb significantly decreased the MMP-3 mRNA level (P < 0.05). MMP-3 mRNA and protein levels decreased in the EGb-treated group, especially in the high-dose group, compared to those in the dexamethasone group (P < 0.05). EGb may reduce MMP-3 production during IL-1ß-induced chondrocyte damage and protect chondrocytes to some extent, with better efficacy at high doses.

Comparative proteomic analysis of the nucleus accumbens during extinction and reinstatement of morphine dependence / Análisis proteómico comparativo del núcleo accumbens durante laextinción y recaída de la dependencia a la morfina

BACKGROUND: The aim of this study was to detect differentially expressed proteins in the nucleus accumbens between the states of extinction and reinstatement of morphine addiction. Numerous studies on the neurobiological mechanisms concerning drug craving and relapse have been reported to date, but data on their relationship with the underlying key molecular mechanisms involved remain limited. METHODS: In this study, 40 male SpragueDawley rats were equally randomized into a saline group and a morphine group. Both groups received drug selfadministration training, after which extinction models were established naturally. The groups were further divided into two subgroups for extinction and reinstatement tests. Cerebral nucleus accumbens masses were measured for total protein extraction. Twodimensional electrophoresis was performed to determine differential protein spots. These differential proteins were then enzymolysed and identified using mass spectrography. RESULTS: The proteins were classified as fatty acidbinding protein, serine/threonine protein phosphatase 2A catalytic subunit beta isoform, serine/threonine protein phosphatase 2A catalytic subunit alpha isoform, serine/threonine protein phosphatase 2A regulatory subunit B² subunit gamma or heat shock protein 90 cochaperone CDC37. CONCLUSION: Significant changes in five proteins were detected between extinction and reinstatement. These proteins are correlated with phosphorylation and the tricarboxylic acid cycle.

ANTECEDENTES: El objetivo de este estudio fue detectar las proteínas diferencialmente expresadas en el núcleo accumbens entre los estados de extinción y recaída de la adicción a la morfina. Hasta la fecha se han reportado numerosos estudios en relación con los mecanismos neurobiológicos del deseo incontenible y recaída en el consumo de drogas, pero los datos sobre su relación con los mecanismos moleculares fundamentales subyacentes implicados, siguen siendo limitados. MÉTODO: En este estudio, 40 ratas machos SpragueDawley fueron por igual asignadas de manera aleatoria a un grupo salino y un grupo de morfina. Ambos grupos recibieron entrenamiento de autoadministración de drogas, después de lo cual se establecieron modelos de extinción de manera natural. A su vez, los grupos fueron luego subdivididos en dos subgrupos para realizar pruebas de extinción y recaída. Se procedió a medir las masas cerebrales del núcleo accumbens para la extracción total de proteína. Se realizó una electroforesis bidimensional para determinar manchas proteicas diferenciales. Estas proteínas diferenciales fueron entonces sometidas a enzimólisis e identificadas mediante espectrografía de masa. RESULTADOS: Las proteínas fueron clasificadas como proteína de unión a ácidos grasos, isoforma beta de la subunidad catalítica serinatreonina proteína fosfatasa 2A, isoforma alfa de la subunidad catalítica serinatreonina proteína fosfatasa 2A, subunidad gamma subunidad B" de la serinatreonina proteína fosfatasa 2A, o la proteína CDC37 cochaperona 90 de choque térmico. CONCLUSIÓN: Se detectaron cambios significativos en cinco proteínas entre la extinción y la recaída. Estas proteínas están correlacionadas con la fosforilación y el ciclo del ácido tricarboxílico.

Comparative proteomic analysis of the nucleus accumbens during extinction and reinstatement of morphine dependence.

BACKGROUND: The aim of this study was to detect differentially expressed proteins in the nucleus accumbens between the states of extinction and reinstatement ofmorphine addiction. Numerous studies on the neurobiological mechanisms concerning drug craving and relapse have been reported to date, but data on their relationship with the underlying key molecular mechanisms involved remain limited. METHODS: In this study, 40 male Sprague-Dawley rats were equally randomized into a saline group and a morphine group. Both groups received drug self-administration training, after which extinction models were established naturally. The groups were further divided into two subgroups for extinction and reinstatement tests. Cerebral nucleus accumbens masses were measured for total protein extraction. Two-dimensional electrophoresis was performed to determine differential protein spots. These differential proteins were then enzymolysed and identified using mass spectrography. RESULTS: The proteins were classified as fatty acid-binding protein, serine/threonine protein phosphatase 2A catalytic subunit beta isoform, serine/threonine protein phosphatase 2A catalytic subunit alpha isoform, serine/threonine protein phosphatase 2A regulatory subunit B2 subunit gamma or heat shock protein 90 co-chaperone CDC37. CONCLUSION: Significant changes in five proteins were detected between extinction and reinstatement. These proteins are correlated with phosphorylation and the tricarboxylic acid cycle.

In vitro induction of tetraploid garlic with trifluralin.

Garlic (Allium sativum) is propagated asexually. Since sexual cross breeding is almost impossible, means for effective breeding are not currently available and the available production cultivars are seriously aged and degenerated. A possible alternative for breeding is chemical induction. Trifluralin, a type of herbicide, has been reported to provoke chromosome doubling. However, this chemical had not been tested on garlic. We tested various trifluralin concentrations and treatment durations for efficiency in the induction of tetraploid garlic. A clove base of garlic with a stem cv. Gailiang was used as the ex-plant to induce calluses on Murashige and Skoog (MS) medium; the calluses were then inoculated onto MS medium containing different levels of trifluralin and cultured to induce chromosome number variation in vitro. Garlic calluses were effectively induced via the ex-plant and both shoots and roots differentiated well on MS medium containing 6-benzylaminopurine at 3.0 mg/L and indole-3-acetic acid at 0.1 mg/L. However, increases in trifluralin concentration and treatment duration reduced the survival rate and differentiation rate of calluses. Garlic callus cultured for 15 days on medium containing 100 µM trifluralin gave the highest rate of chromosome doubling. Through observation of chromosome number in the root apical cells and the morphology of guard cells on the leaf epidermis of the regenerated plantlets, it was clear that chromosome number variation was induced and tetraploids were produced in vitro by trifluralin treatment.

Secondary potential in electrodialysis membranes and the effect on permselectivity.

The most important factor in the electrodialysis (ED) process is the permselectivity of the ion exchange membranes, which permit not only the separation of cations and anions in a solution, but also the separation of ions with the same sign but different valences. In this work, the mechanism of the permselectivity has been studied through the measurement of the potentials at different planes of the membrane. The experimental results have shown that there was a secondary potential inside ion exchange membranes in an electrodialysis process. At the membrane side touched with dilute solution, this secondary potential enhanced the external electrical field, and thus speeded up the passage of the corresponding ions in the dilute solution through the membranes; at the membrane side touched with concentrated solution, the secondary potential was contrary to the external electrical field and thus counteracted it, which could be very helpful by preventing the ions in the concentrated solution from entering the membranes. Obviously, the existence of the secondary potential might play an important role in the permselectivity of ion exchange membranes in ED processes.